Bobbin-holding device.



P. R. HATCH.

BOBBIN HOLDING DEVICE. APPLICATION FILED MAR. 10, 1910.

1,015,023, Patented Jan. 16, 1912.

rinrrnn STATES PATENT cur os.

FRANK R. HATCH, OF HAVERHILL, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY,

JERSEY.

A CORPORATION OF NEW BOBBIN-HOLDING DEVICE.

To all whom it may concern:

Be it known that I, FRANK R. I-IA'roH, a citizen of the United States, residing at Haverhill, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Bobbin-Holding Devices; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to an improvement in bobbin holders for lock stitch sewing machines.

In the Goodyear Rapid stitcher, which is illustrated with substantial accuracy in the patent to French and Meyer, No.47 3,870, the bobbin case, or bobbin, as the bobbin and bobbin case are generally referred to, is placed loosely in the oscillating shuttle and held there during the operation of the machine by a bobbin holding arm which engages the face of the bobbin and prevents its displacement. For convenience in removing and replacing the bobbin the bobbin holding arm is pivoted to a bolt supported in a bracket from the side of the shuttle race. By tightening the nut on the bolt the bobbin holding arm is frictionally held in place. A leather washer under the nut is relied upon to create the necessary friction to hold the .bobbin arm from displacement .in the operation of the machine. The construction constitutes an embodimentof the invention described in the patent to French and Meyer, No. 424,966, from theillustrated embodiment of which, however, it differs in that the bolt is extended upward through the arm and the bracket on the frame and the nut on the upper end is provided with a handle. The nut and bolt are threaded lefthand, so that in turning the handle to loosen the nut, after the nut has become slightly loosened, the friction between the parts is suflicient to enable the operator by the continued turning of the handle to open the bobbin holding arm, thus swinging itaway from the bobbin so that the bobbin may be removed from the shuttle. These means for operating the bobbin holding arm to open and close it and to hold it closed have been found ineffective to some degree owing to the fact that because friction is depended upon to operate and hold the arm in place, the jar 5 incident to the operation of the machine,

and particularly the jar of the bobbin Specification of Letters Patent.

Application filed March 10, 1910.

Patented Jan. 16,1912.

Serial No. 548,466.

against the arm, tends to loosen the nut which holds the arm in place.

The objects of the present invention are to reorganize and improve the construction and operation of bobbin holding means of the character referred to.

The features of the invention relate, therefore, to certain devices, combinations and arrangements of parts hereinafter described and claimed, which possess advantages in simplicity of construction and ease of operation which will be apparent to those skilled in the art.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which-4 Figure 1 is a front elevation of the shuttle race and bobbin holding means; Fig. 2 is a plan of the parts shown in Fig. 1 taken on the line 22 of that figure; Figs. 3 and 4 are fragmentary sections on the line 33 of Fig. 1 showing the locking means, for the bobbin holding arm when said arm is closed and opened; and Figs. 5 and 6 are details, in underside plan, and elevation, respectively, showing the means by which the bottom arm locking means is caused to act properly in all positions of adjustment of the arm.

In the embodiment of the invention illustrated in the drawings, the shuttle race 1 adapted to receive the shuttle 2, and within the shuttle the bobbin 8, is substantially the same as in the patented machine hereinbefore referred to. The bobbin holding arm 4 is journaled upon the lower end of the bolt 5 below a lug 6 projecting from the shuttle race in which lug the bolt is secured. A stop screw 7, provided with a set nut, is threaded into an aperture in the arm 4, and is adapted to engage the periphery of the shuttle race, or other part of the rigid frame, to limit the inward or closing movement, of the arm. The screw 7 is preliminarily adjusted to allow sufficient clearance between the bobbin and bobbin holding arm to permit the free movement of the bobbin and the passage of the thread between the parts.

Means is provided for opening and closing the bobbin holding arm and for locking it in its closed position. To this end a bracket 8 is secured to the machine frame by means of screws 9 (dotted lines Fig. 1) and a support 10 on the bolt 5. This bracket is provided with a split sleeve 11 having secured therein a key 12 adapted to enter an axial keyway 13 (Fig. 4) in a vertically arranged support 14, preferably a shaft, within the sleeve. This arrangement constrains the shaft to a vertical axial movement eX- cept under a certain construction which will be hereinafter explained. The shaft is provided with a head or handle 15 and a grasshopper spring 16 is arranged between the head and bracket normally maintaining the shaft in its raised position. The upward limit of movement of the shaft is determined by an enlarged head 17, at its lower end. This head is formed with a beveled cam face 18 (Figs. 1 and 4) adapted to engage with a surface contact an oppositely beveled cam face 19 (Figs. 3 and 4) on the journal of the bobbin holding arm 4. The bevels on the faces 18 and 19 are so directed that the spring 16 causes the cam face 18 to act as a wedge when the faces engage each other. hen the beveled cam faces 18 and 19 are in engagement, as shown in Figs. 1 and 3, the arm 4 is held positively and unyieldingly, under ordinary conditions, in its closed position by their wedging action and surface contact, the inward limit of its movement being determined by the stop screw 7. When the shaft 14 is depressed by the operative and its head 17 moved to the dotted line position shown in Fig. 1, a suitably coiled spring 20 (Figs. 1 and 2) operates to open the bobbin holding arm. The opening movement causes an enlargement 21 on the journal of the arm to pass above the shaft head 17 (see Fig.4) so that when the shaft is released its spring 16 operates to clamp said enlargement between the head 17 and lug 6 and assist the spring to hold the arm open. To close the bobbin holding arm it is merely necessary to push it inward about its fulcrum 5 until the cam face 19 is substantially parallel to the cam face 18 when the spring 16 is permitted to raise the shaft 14 and by reason of the wedging action exerted on the cam face 19 seat the stop screw 7 firmly against the shuttle race and lock the arm securely in the position thus determined. An important advantage of this construction is found in the simplicity of operation. A single blow on the handle 15 automatically opens and holds open the bobbin holding arm permitting the operative to use both hands in manipulating the bobbin. A single blow on the arm 4 closes and automatically locks the arm in closed position. A further advantage of this construction resides in the fact that it provides for always seating the stop screw, and thus holding the arm in the desired inward position, by reason of the fact that it automatically takes up the wear between the contacting cam faces. It is obvious that the spring 16 will invariably cause the wedging action of the shaft head 17 to conoifers another advantage.

tinue, whatever the wear of the cam faces, until the upward movement of the shaft is stopped by the engagementof the stop screw with the shuttle race. The preferred arrangement of the cam faces for maintaining the bobbin holding arm in closed position While the construction and arrangement of the illustrated embodiment of the invention provides a lock for the arm which will not permit the jarring of the machine to work the arm outward away from the bobbin, it nevertheless permits the arm to yield away from the bobbin under unusual outward strains, placed upon it, which, if the arm were held rigidly in closed position, would cause breakage. For instance, when a jamming of the thread, or a sudden stopping of the machine from some cause, places an excessive outward strain on the bobbin holding arm, the vertical angular relation of the beveled cam faces 18 and 19, held yieldingly together by the spring 16, permits the faces to slide past each other and the arm to move outward slightly in response to such strain, the spring returning the arm to its proper closed position as soon as normal conditions are resumed.

Referring now again to Fig. 4, it will be seen that when the bobbin holding arm is moved to its inward position, in the direction of the arrow, the corner 0 of the enlargement 21 is the first part of the cam face 19 to be engaged by the upwardly moving cam face 18. This condition causes an excessive wear on the corner 0 and is apt, after a time, to form a surface at an angle to the surface of the cam face 19 against which the cam face 18, owing to its inability to move angularly, seats itself before the stop screw engages the shuttle race. The arm, under these conditions, is held somewhat outward from the desired closed position by the spring 20 and permits an undesirable loose play between the bobbin and its holding arm. To obviate this condition the keyway 13 may be formed at 13 (Fig. 6) somewhat wider than the thickness of the key 12 thus permitting a limited angular movement of the shaft 14 within the sleeve 11. WVith this 1 5 6) until the cam faces come into surface contact, at which time the stop screw 7 has seated itself, the shaft thereafter moving upward without further angular movement. Such an arrangement effectually prevents wear of the corner 0 and the undesirable effects caused by such wear.

The invention is applicable to different forms of lock stitch sewing machines than that shown in the patent hereinbefore re far d e a di i to nde t o h t 136 While in the claims a bobbin is referred to as the device which is adapted to be held in place by the bobbin holding arm, the invention is not limited to the use of a bobbin as it is within the contemplation of the invention to apply the construction to sewing machines in which the entire shuttle is held in position by a holder.

The nature and scope of the presentinvention having been indicated and the preferred embodiment of the invention having been specifically described, what is claimed as new is 1. A lock stitch sewing machine, having, in'combination, a bobbin, a pivotally mounted bobbin holding arm, a movable locking device for holding said arm in closed position, means for automatically opening the arm when the device is removed from locking position, and means for holding the locking device in inoperative position while the arm remains in open position.

2. A lock stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm, a movable locking device for holding said arm in closed position, means for automatically opening the arm when the device is removed from locking position, and clamping means for bold ing the arm in open position.

8. A look stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm, a cam to lock the arm in closed position and held in inoperative position when the arm is in open position, and means for automatically moving said cam into locking position when the arm is closed by the operative.

4. A lock stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm, a spring to move the arm from closed to open position, a locking cam arranged to engage the, arm and lock it in closed position, and -means to move said cam out of locking position to permit the spring to open the arm.

5. A lock stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm, an axially movable shaft extending transversely of the plane of movement of the arm, and a cam carried by the shaft arranged to engage the arm and lock it in closed position.

6. A lock stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm having a beveled cam face and an axially movable shaft having a complemental beveled cam face, said cam faces being arranged to engage and disengage eachother on movements of the shaft in opposite directions to lock and unlock the arm.

7 A lock stitch sewing machine, having,

Copies of this patent may be obtained for in combination, a bobbin, a pivotally mounted bobbin holding arm having a stop screw arranged to seat itself against the rigid frame and determine the inward limit of movement of the arm, a lineally movable support having a beveled cam face mounted adjacent said arm, a complemental beveled cam face on the arm, said cam faces being arranged to be placed in parallelism when the stop screw is seated, and means for moving said support to cause engagement of the cam faces and to wedge said arm in closed position.

8. A look stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm having a stop screw arranged to seat itself against the rigid frame and determine the inward limit of movement of the arm, a movable shaft eX- tending transversely of the plane of movement of the arm, and cam faces on the arm and shaft adapted to be brought into engagement by an axial movement of the shaft and form an arm-locking contact when the stop screw is seated.

9. A look stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm having a cam face, a lineally movable support having a complemental cam face to engage the cam face on the arm when said arm is in closed position, and a spring acting on the last named cam face to cause it to engage the first named cam face whatever the wear of the parts.

10. A look stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm adapted to swing into and out of bobbin holding position, a beveled cam face on the arm, a second beveled cam face mounted in the frame acting on the first cam face in a direction to hold the arm in closed position, and means for yieldingly holding said cam faces in sliding engagement when the arm is in closed position.

11. A lock stitch sewing machine, having, in combination, a bobbin, a pivotally mounted bobbin holding arm adapted to swing into and out of bobbin holding position, a spring pressed lineally movable support adjacent the arm, and complemental beveled cam faces on the arm and support in engagement when the arm is in closed position, whereby, under an excessive outward strain on the arm, the yieldingly mounted cam face slides past the other and permits the arm to move outward slightly.

FRANK R. HATCH.

Witnesses:

DARREN G. OGDEN, RUTH A. SIMoNDs.

five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

